I am implementing Sitecore and looking to get Sitecore certification which should help us develop solutions and better architect integrations around it. When I search for certification for the developer, I found there are 2 available on site:

Sitecore® Experience Solution Developer 9.1

Implementing Sitecore Experience Commerce™ 9.0.1

Can anyone help to understand the differences and assist what are the pre-requirement for Training and what i prepare before the training?

I would like to get some articles ahead of time if we can play/learn before it.

Hello Nick,
If you are Sitecore commerce background, then you should go with "Implementing Sitecore Experience Commerce™ 9.0.1 ", but according to me you should first clear the Certificate of "Sitecore® Experience Solution Developer 9.1" before Commerce specific. You can follow following links to get study material for
"Sitecore® Experience Solution Developer 9.1" certificate exam: